Cell Genesys Inc announced that it has received a Special Protocol Assessment (SPA) from the US FDA for its upcoming Phase 3 clinical trial of GVAX prostate cancer vaccine.

The SPA indicates that the trial will adequately address the objectives necessary to support a biologics license application (BLA) and that the study forms the basis for a definitive assessment of the effectiveness of the vaccine. This trial will be the first of two Phase 3 trials of GVAX prostate cancer vaccine targeting hormone-refractory, metastatic prostate cancer.

The SPA is a process that allows for official FDA evaluation of a Phase 3 clinical trial whose data will form the primary basis for an efficacy claim and provides trial sponsors with binding written agreement that the design and analysis of the study are adequate to support a license application submission if the study is performed according to the SPA. The SPA agreement may only be changed by the sponsor company or the FDA through a written agreement, or if the FDA becomes aware of a substantial scientific issue essential to product efficacy or safety.

"We are very pleased to be able to report the agreement we have reached with FDA in our Phase 3 development program," stated Joseph J. Vallner, Ph.D., president and chief operating officer of Cell Genesys. "We look forward to initiating the first Phase 3 clinical trial of GVAX prostate cancer vaccine and are continuing to make good progress toward achieving our goal of beginning this trial by the end of the second quarter. We hope that this product may one day benefit patients with prostate cancer."

"The SPA provides Cell Genesys with a clear pathway toward regulatory submission for our lead product candidate, GVAX prostate cancer vaccine, and we are pleased to have obtained this agreement with the FDA," stated Carol G. Grundfest, vice president, regulatory affairs and project management at Cell Genesys. "FDA worked very closely with us during the entire SPA process, and the dialogue we have had with the agency has been highly productive."

Cell Genesys plans to conduct two Phase 3 clinical trials of GVAX prostate cancer vaccine in hormone-refractory prostate cancer patients with radiologic evidence of metastatic disease. The first trial (VITAL-1 or Vaccine ImmunoTherapy with Allogeneic prostate cancer cell Lines) will enroll chemotherapy naïve, asymptomatic patients without cancer-related pain and will compare GVAX vaccine to taxane chemotherapy with respect to survival benefit.

The second trial (VITAL-2), which is expected to begin in the late 2004/early 2005 timeframe, will enroll symptomatic patients and will compare GVAX vaccine plus taxane chemotherapy to taxane chemotherapy alone with respect to palliation of bone pain. Both trials will enroll patients with all levels of Gleason scores (a measure of the aggressiveness of prostate cancer) including the highest risk patients.